Re: [STDS-802-11-TGM] 11me/D1.0 CID 1859 (all-zero Classifier Mask field

Thread Links	Date Links
Thread Prev	Thread Next	Thread Index	Date Prev	Date Next	Date Index

Thanks for reminding me of this additional horror. This corresponds

to CIDs 2026 to 2029, probably specifically 2026 here.

Can you help with 2026 in terms of identifying when the User Priority

field is an input (i.e. part of what is used to classify)

and when it is an output? Then maybe the NOTE could read:

A classifier classifies on the basis of at least one match.

NOTE---For example, when the Classifier Mask field is present and

not reserved, at least one bit of this field that is not reserved is set to 1,

unless the User Priority field is used to classify and is not set to 255.

> given the Frame Classifier field must be present

Note though that the Classifier Mask subfield is not present in classifier

type 10 (see the second half of CID 1856).

Thanks,

Mark

Mark RISON, Standards Architect, WLAN English/Esperanto/Français

Samsung Cambridge Solution Centre Tel: +44 1223 434600

Innovation Park, Cambridge CB4 0DS Fax: +44 1223 434601

ROYAUME UNI WWW: http://www.samsung.com/uk

From: Thomas Derham <thomas.derham@xxxxxxxxxxxx>
Sent: Thursday, 17 February 2022 17:10
To: Mark Rison <m.rison@xxxxxxxxxxx>
Cc: STDS-802-11-TGM@xxxxxxxxxxxxxxxxx; Jouni Malinen (jouni@xxxxxxxxxxxxxxxx) <jouni@xxxxxxxxxxxxxxxx>
Subject: Re: 11me/D1.0 CID 1859 (all-zero Classifier Mask fields)

Hi Mark

In general this looks OK to me, but I recall a previous discussion about whether the User Priority field in TCLAS element is an “input” or “output”, which could be relevant here.

In cases where the UP is an “output” (i.e. that UP is assigned to MSDUs that match the filter), it probably makes sense that the Frame Classifier field is not completely wildcard (although I’m not sure it hurts to allow that possibility).

OTOH, in the specific case of TFS which was identified in the previous thread, it seems the UP field (when it takes values 8 thru 11) is an *input* for MPDU classification, i.e. it’s effectively part of the classifier itself. Then, might there be a use case where the only required filter is the AC of the MPDU, and no other filters (e.g. MAC addresses, IP tuples) is necessary? If so, given the Frame Classifier field must be present, it might need to specify a wildcard classifier..

Thanks

Thomas

On Feb 17, 2022, at 2:53 AM, Mark Rison <m.rison@xxxxxxxxxxx> wrote:

I haven't seen any response to this post, so should I conclude that

there is no objection to resolving this comment as:

REVISED

At the end of 9.4.2.30 add:

A classifier classifies on the basis of at least one match.

NOTE---For example, when the Classifier Mask field is present and

not reserved, at least one bit of this field that is not reserved is set to 1.

?

Thanks,

Mark

--

Mark RISON, Standards Architect, WLAN   English/Esperanto/Français

Samsung Cambridge Solution Centre       Tel: +44 1223 434600

Innovation Park, Cambridge CB4 0DS      Fax: +44 1223 434601

ROYAUME UNI                             WWW: http://www.samsung.com/uk

From: Mark Rison
Sent: Friday, 21 January 2022 21:00
To: 'STDS-802-11-TGM@xxxxxxxxxxxxxxxxx' <stds-802-11-tgm@xxxxxxxxxxxxxxxxx>
Cc: Thomas Derham (thomas.derham@xxxxxxxxxxxx) <thomas.derham@xxxxxxxxxxxx>; Jouni Malinen (jouni@xxxxxxxxxxxxxxxx) <jouni@xxxxxxxxxxxxxxxx>
Subject: 11me/D1.0 CID 1859 (all-zero Classifier Mask fields)

I was asked to start a thread on this comment:

CID 1859

9.4.2.30

It is not clear whether it is OK to have a Classifier Mask field (where it is not reserved) that is all-0, and if so whether that is an "always matches" or a "never matches"

At the end of the subclause add "If a Classifier Mask field is present and all bits that are not reserved are 0, then this classifier never matches."

As far as I can tell, the classifiers have the following classifier

masks:

0, 1, 2, 4, 5: bitmap indicating parameters that need to match

6, 7, 8, 9: bitmap with 2-bit subbitmaps

3: reserved

10: not present (despite what Figure 9-364—Frame Classifier field format says -- see CID 1856)

The direction of the group was to specify that classifiers that

don't classify anything shall not be transmitted, rather than

trying to specify that they never or always match.

Because there are so many classifiers, and they classify in quite

significantly different ways, I propose adding this general statement

at the end of 9.4.2.30:

A classifier classifies on the basis of at least one match.

NOTE---For example, when the Classifier Mask field is present and

not reserved, at least one bit of this field that is not reserved is set to 1.

Thanks,

Mark

--

Mark RISON, Standards Architect, WLAN   English/Esperanto/Français

Samsung Cambridge Solution Centre       Tel: +44 1223 434600

Innovation Park, Cambridge CB4 0DS      Fax: +44 1223 434601

ROYAUME UNI                             WWW: http://www.samsung.com/uk

To unsubscribe from the STDS-802-11-TGM list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-11-TGM&A=1

Re: [STDS-802-11-TGM] 11me/D1.0 CID 1859 (all-zero Classifier Mask fields)